1. Field of the Invention
The present invention relates to archery equipment and, more particularly, to nocks for use with arrows.
2. Description of Related Art
In the field of modem archery, the rear end of an arrow includes a notch for receiving the bowstring. Usually, the notch is defined by a permanently attached nock. The nock includes a hollow end for receiving the end of the arrow shaft. If the shaft is tubular, the nock may include a stud for insertion into the shaft. Other variants for attaching the nock to the shaft exist.
The notch of the nock is formed by a pair of rearwardly extending wings for receiving the bowstring therebetween. These wings usually include opposed inwardly extending protrusions for gripping the bowstring as the bowstring is drawn back and released, whether by one's fingers or by a mechanical triggering element. Generally, the bowstring includes a nocking point formed by dental floss, light thread, or yarn wrapped around the bowstring. Various commercially available sleeves may be attached about the bowstring to serve as a nocking point.
Since the bowstring is drawn back by engaging the bowstring itself, not the arrow, there is some danger of the arrow shaft disengaging from the bowstring unless the nock firmly grips the bowstring. Such gripping is provided by the protrusions discussed above. Upon release of the bowstring, the arrow accelerates rapidly in the direction of flight. The resulting momentum of the arrow causes the nock to release from the bowstring at the end of forward travel of the bowstring. The resulting resistance to forward movement of the arrow caused by the arrow overcoming the clamping action of the nock to effect release of the arrow decelerates the arrow to an extent which is a function of the gripping force exerted by the nock. Such deceleration negatively affects the speed of the arrow and hence distance traveled. Moreover, the sudden deceleration may set up a quiver or vibration of the arrow shaft along its length which affects its aerodynamic properties, and increases air resistance. The vibrating arrow shaft may also affect the accuracy of its expected trajectory. By reducing the clamping force of the nock, inadvertent disengagement of the nock from the bowstring is to be expected under field conditions. Such disengagement is unacceptable in a hunting environment. This result may even cause a life-threatening situation if the animal being hunted is prone to attack the archer.